Structure and magnetic properties ofhigh-performanced Sm2（Co, Fe, Cu, Zr）17 alloys

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成分对高温永磁体Sm(CoFeCuZr)z显微组织和磁性能的影响

成分是影响Sm(CoFeCuZr)z性能的关键因素之一。本文概述了成分对高温永磁体Sm(CoFeCuZr)z显微组织和磁性能影响的研究状况。并指出了掌握成分与显微组织和磁性能的关系，对制造高性能高温永磁体Sm(CoFeCuZr)z的现实意义。     

NdFeB稀土永磁材料的研究现状

NdFeB稀土永磁材料由于具有优异的磁性能而受到人们的广泛关注.系统地介绍了Nd-FeB的微观结构、矫顽力机制、腐蚀机理及其防护、高性能磁体的制备新工艺等,提出了今后的研究和发展方向.     

纳米晶高密度钨合金的研究进展

介绍了近几年来纳米晶钨基高密度合金的研究状况,讨论了粉末制备的机械合金化法、喷雾干燥法和反应喷射工艺法,同时详细讨论了粉末的注射成形以及包括固相烧结、二步烧结在内的烧结工艺.最后,从这些方面分析了影响纳米晶钨合金性能的具体因素,以及对高密度钨合金今后的发展方向提出了建议.     

超导体MgB2超导电性及制备技术的研究进展

介绍了新型超导体MgB2的基本超导电性,综述了MgB2材(多晶)、线材和带材的主要制备技术,并对MgB2超导材料的应用前景进行了展望.     

粉末冶金温压工艺的研究进展及展望

温压是一项以较低的成本制造高性能粉末冶金零件的新型成形技术，本文综述并讨论了温压工艺的粉末原料、聚合物、温度、压力、烧结环节及致密化机理。在此基础上，介绍了温压工艺的新发展——流动温压、高压温压等，并对其应用前景进行了展望。     

烧结工艺对高温Sm(Co,Fe,Cu,Zr)z永磁体磁性能与显微组织的影响

用粉末冶金法制备了Sm(Co0.7Fe0.1Cu0.16Zr0.04)6.7烧结磁体,设计了8种不同烧结工艺;并对磁体的磁性能在烧结过程中的变化以及烧结工艺条件与显微组织的关系进行了系统研究.结果表明适当提高预烧结温度与烧结温度有利于磁性能的改善,但预烧结温度与烧结温度过高或过低都会使磁性能大大降低.矫顽力对烧结工艺非常敏感;样品在1 185℃预烧结后再在1 200℃烧结有最好的综合磁性能,其内禀矫顽力高达1 931 kA/m.还用扫描电子显微镜、电子探针光谱仪对显微组织及元素分布进行了分析,结果表明磁性能的改变可以认为是显微组织变化与元素在各相中分布变化的结果.     

Effects of warm compaction on mechanical properties of sintered P/M steels

The green and sintered densities,and tensile strength of sintered P/M steels produced by cold compaction,warm compaction,warm compaction combined with die wall lubrication(DWL)were measured under various compaction pressures using polytetrafluoroethylene(PTFE)emulsion as the die wall lubricant.The effects of warm compaction on the mechanical properties were studied.The tensile fracture behaviors of cold compaction and warm compaction were studied using scanning electron microscope(SEM).The results show that the density of sintered P/M steel prepared by warm compaction or warm compaction with DWL is higher than that by cold compaction under all compaction pressures.Meanwhile,the highest tensile strength is obtained by combination of warm compaction and die wall lubrication under all compaction pressures.The SEM results show that the fracture modes of the sintered samples prepared by cold compaction and warm compaction at 700 MPa are the mixed mode of ductile fracture and brittle fracture,and obvious dimples can be found in some regions.The fracture of sample prepared by cold compaction is uneven and has irregular and big pores,but that by warm compaction is relatively even and the pores are round mostly,and the samples have many obvious dimples on the whole fracture surface.     

成分对高温永磁体Sm(CoFeCuZr)_z显微组织和磁性能的影响

成分是影响Sm(CoFeCuZr) z 性能的关键因素之一。本文概述了成分对高温永磁体Sm(CoFeCuZr) z 显微组织和磁性能影响的研究状况。并指出了掌握成分与显微组织和磁性能的关系 ,对制造高性能高温永磁体Sm(CoFeCuZr) z 的现实意义。     

2Mo81Ni17Fe磁粉芯磁导率的工艺影响因素

本文以氮气雾化2Mo81Ni17Fe合金粉末为原料,采用粉末冶金方法制备了2Mo81Ni17Fe磁粉芯,测试了磁粉芯的磁导率.主要讨论了磁粉芯磁导率的影响因素.结果表明,磁粉芯的磁导率随着绝缘剂添加量的增加而减少,随着压制压力以及热处理温度的提高而上升.